File: assume-edge-dom.ll

package info (click to toggle)
llvm-toolchain-17 1%3A17.0.6-22
  • links: PTS, VCS
  • area: main
  • in suites: forky, sid, trixie
  • size: 1,799,624 kB
  • sloc: cpp: 6,428,607; ansic: 1,383,196; asm: 793,408; python: 223,504; objc: 75,364; f90: 60,502; lisp: 33,869; pascal: 15,282; sh: 9,684; perl: 7,453; ml: 4,937; awk: 3,523; makefile: 2,889; javascript: 2,149; xml: 888; fortran: 619; cs: 573
file content (39 lines) | stat: -rw-r--r-- 914 bytes parent folder | download | duplicates (14) 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
 
; RUN: opt -S -passes=jump-threading < %s | FileCheck %s

declare ptr @escape()
declare void @llvm.assume(i1)

define i1 @test1(i1 %cond) {
entry:
    br i1 %cond, label %taken, label %not_taken

; CHECK-LABEL: @test1
; CHECK: br i1 %cond, label %no, label %yes
; CHECK: ret i1 true

taken:
    %res1 = call ptr @escape()
    %a = icmp eq ptr %res1, null
    tail call void @llvm.assume(i1 %a)
    br label %done
not_taken:
    %res2 = call ptr @escape()
    %b = icmp ne ptr %res2, null
    tail call void @llvm.assume(i1 %b)
    br label %done

; An assume that can be used to simplify this comparison dominates each
; predecessor branch (although no assume dominates the cmp itself). Make sure
; this still can be simplified.

done:
    %res = phi ptr [ %res1, %taken ], [ %res2, %not_taken ]
    %cnd = icmp ne ptr %res, null
    br i1 %cnd, label %yes, label %no

yes:
    ret i1 true
no:
    ret i1 false
}